Brown anthraquinone dye and process of making same.



UNITED STATES FATE cri ics.

RUDOLF UHLENHUTH, or Hocrrs'r-oN-THE-MAIN, GERMANY, ASSIGNOR TO BARB- WERKE VORM. MEISTER LUCIUS & BRUNINQ OF HUCHST-ON-THEJVIA-ITN, GERMANY,

A CORPORATION OF GERMANY.

BROWN ANTHRAQI TINONE DYE AND PROCESS OF MAKING SAME.

No Drawing.

To all a r/tom it may concern:

Be it known that I, RUDoLF UHLENHU H, Ph. DI, chemist, a citizen of the Empire of Germany, residing at HZichst-on-the-Maim' Germany, have invented certain new and useful Improvements in the Manufacture of New Brown Anthraquinone Dyestuffs, of which the following is a specification.

Myinvention relates tothe manufacture of new anthraquinone derivatives dyeing in the rat, by melting with alkalies the dialithraquinonyl.1.4 diamidoanthraquinones of the general formula:

Ten parts by weight of di-alpha-alpha-anthraquinonyll. l-diamidoanthraduinone, obtainable for instance from IA-dianiidoanthraquinone and alpha-chloroanthraquinone, are introduced at about 180 centigrade into 100 parts of fused caustic potash and then the temperature is raised to 216 centigrade. The reaction product finally separates'out on the surface of the melt and becomes solid.

It is poured into water and filtered. In this way the dyestuflf is obtained in the form of a black powder of the above mentioned Specification of Letters Patent.

Patented Dec. 21, 1909.

Application filed March 24, 1909. Serial No. 485,516.

properties. It dissolves to a brown solution in concentrated sulfuric acid and is precipitated from this solution in brown flakes by addingwater. It dyes cotton in the hydro sulfite .vat. Havana-brown shades.

Having now described my invention and in what manner the same is to be performed,

by Letters-Patent, is:

,"1. The process for producing new anthraquinone dyestuffs, which consists in melting with alkalies the dianthraquinonyl.L l-diamidoanthraquinones of the general formu a: 7

NH anthraquinonyl till -N H euthraqiiinonyl and then isolating the resulting dyestuff from the reaction mixture, substantially as hereinbefore described.

2. The process for producing a new anthraquinone dyestuff which consists immelting with alkalies di-alpha-alpha-anthraqninonyl.1. L-diamidoanthraquinone and then isolating the resulting dyestuif from the reaction mixture, substantially as hereinbefore described. r I 3. As new products, the herein described new dyestuffs, obtainable by melting di; anthraquinonyLLt diamidoanthraquinones are dark powders insoluble in water, in alkable in the usual organic solvents, dyeing cotton from the vat fast brown shades, substantially as hereinbefore described.

4. As a new product, the herein described new dyestufl, obtainable by melting dialpha alpha anthraquinonyl.lAc-diamidoanthraquinone with alkalies, which dyestuli, when dry, is a dark powder, being insoluble in water in 'alkalies and diluted acids, and

what I claim as new, and desire to secure with alkalies, which dyestufls, when dry,

lies and in diluted acids, and very little soluvery little soluble in the usual organic solallmlies, substantially as hereinbefore devents; being dissolved by concentrated sulscribed. 10

furic acid (of 66 B.)' yielding a brown In testimony whereofll afiix my signature solution from which the dyestufi separates in presence of two Witnesses.

out in brown flakes on the addition of Water, RUDOLF UHLENHUTH. dyeing cotton in the hydrosulfite vat Ha- WVitnesses: rum-brown shades which are very fast to JEAN GRUND,

:.he light and resist very Well chlorin and CARL GRUND. 

